K Levels

The Medicare Functional Classification Level (MFCL) K level is a 0 to 4 scale that classifies the current ability or the potential that an amputee may have for reaching a certain level of mobility and function (Orendurff et al., 2016). This may be used as a guide for what type of prosthesis the amputee is appropriate for based on their needs and the potential benefit that the prosthesis could have on their mobility and quality of life (Nelson et al., 2006). The descriptions of the five levels can be seen in the table below.

Higher K levels indicate that a patient has a greater potential to be more active, ambulate in the community with variable cadence, and participate in activities that require greater demands than simple ambulation (Orendurff et al., 2016). Therefore these higher K level amputees will be more appropriate for more technologically advanced and expensive prostheses, such as microprocessor knees and ankles, and carbon fibre prosthetic feet (Orendurff et al., 2016). Conversely, lower K levels are non-ambulant or have limited potential for variable cadence and navigating the community, and therefore are likely to be more appropriate for less advanced prosthetic knees and feet (Orendurff et al., 2016).

The decision is made by the physician and the prosthetist based on an evaluation of the patient’s past history, current history and condition of the residual limb, and their ambulation goals (Gailey et al., 2002). There are no standards for this assessment and there may be differences in the interpretation of the definitions of the functional level characteristics (Orendurff et al., 2016). However, the AMPPRO and AMPnoPRO are valid and reliable measures for assessment of function and mobility that may be used to help determine the patient’s potential ambulatory level (Gailey et al., 2002).

References:

Gailey, R. S., Roach, K. E., Applegate, E. B., Cho, B., Cunniffe, B., Licht, S., ... & Nash, M. S. (2002). The amputee mobility predictor: an instrument to assess determinants of the lower-limb amputee's ability to ambulate. Archives of physical medicine and rehabilitation, 83(5), 613-627. doi: 10.1053/apmr.2002.32309

Nelson, V. S., Flood, K. M., Bryant, P. R., Huang, M. E., Pasquina, P. F., & Roberts, T. L. (2006). Limb deficiency and prosthetic management. 1. Decision making in prosthetic prescription and management. Archives of physical medicine and rehabilitation, 87(3), 3-9. doi: 10.1016/j.apmr.2005.11.022

Orendurff, M., Raschke, S. U., Winder, L., Moe, D., Boone, D. A., & Kobayashi, T. (2016). Functional level assessment of individuals with transtibial limb loss: evaluation in the clinical setting versus objective community ambulatory activity. Journal of rehabilitation and assistive technologies engineering, 3, 1-6. doi: 10.1177/2055668316636316

Medicare Functional Classification Level

(Gailey et al., 2002; Nelson et al., 2006; Orendurff et al., 2016)

K Level

Description

Non-ambulant. Does not have the ability or potential to transfer or ambulate safely with or without assistance, and mobility and quality of life are not improved with a prosthesis.

Household ambulator. Has the ability or potential to use a prosthesis for transfers or ambulation on level surfaces at fixed cadence. Typical of the limited and unlimited household ambulator.

Has the ability or potential for ambulation with the ability to traverse low level environmental barriers such as curbs, stairs or uneven surfaces. Typical of the limited community ambulator.

Has the ability or potential for ambulation with variable cadence. Typical of the community ambulator who has the ability to traverse most environmental barriers and may have vocational, therapeutic, or exercise activity that demands prosthetic utilization beyond simple locomotion

Has the ability or potential for prosthetic ambulation that exceeds basic ambulation skills, exhibiting high impact, stress, or energy levels. Typical of the prosthetic demands of the child, active adult, or athlete.